Wikipedia talk:WikiProject Physics/Archive December 2012

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Template:Classical Physics

{{Classical Physics}} Where does the nonlinear wave equation in this template appear in classical physics? The speed $c$ is taken as a function of the field $u(\mathbf {x} ,t)$ . This non-linear wave equation does not seem to be generated by a variational principle: for instance a Lagrangian $L={\tfrac {1}{2}}c^{2}(u)\,(\nabla u)^{2}-{\tfrac {1}{2}}\left({\partial u}/{\partial t}\right)^{2}$ leads to ${\partial ^{2}u}/{\partial t^{2}}-\nabla \cdot (c^{2}\,\nabla u)+c\,(\partial c/\partial u)(\nabla u)^{2}=0.$ The form $\nabla \cdot (c^{2}\,\nabla u)$ is quite general if $c$ varies in space. I do not know whether this equation has conserved quantities, which one would expect for a dissipationless system. Is it not wiser to take $c$ (a constant) in the template, instead of $c(u)?$ -- Crowsnest (talk) 23:09, 1 December 2012 (UTC)

Why the wave equation anyway? Wave equations occur in EM, QM and GR... If it's classical mechanics why not just use Newton's law F = dp/dt or (Lagrange's equations, or Hamilton-Jacobi equation, etc.) for the equation? Maschen (talk) 23:13, 1 December 2012 (UTC)

I found the reason why the wave equation is used in this template (see Physics#Core theories). It stays in contrast to Schrödinger's Equation, it's quantum mechanical analog. Patrick87 (talk) 02:16, 2 December 2012 (UTC)

Newton's law sounds like a better choice to me. RockMagnetist (talk) 04:01, 2 December 2012 (UTC)

In the case of classical physics, I would opt for Newton's law: bearing in mind our readership, Newton's laws are widely understood, even at secondary school level. Martinvl (talk) 07:51, 2 December 2012 (UTC)

(To Patrick87), the better QM analogue is the HJE:

-{\dfrac {\partial S}{\partial t}}=H\left(\mathbf {q} ,{\dfrac {\partial S}{\partial \mathbf {q} }},t\right)

I'd be inclined to put this in since it contains all of classical mechanics and is as close to QM as CM gets, but Newton's 2nd law is far more well-known. Maschen (talk) 09:49, 2 December 2012 (UTC)

Why would we want to get as close to QM as we can? Why not celebrate differences, in this era of increasing tolerance? RockMagnetist (talk) 19:49, 2 December 2012 (UTC)

It's such a trivial change I thought to just do it. It's not about how close CM approaches to QM, just that the HJE has such nice properties (at least IMO)... Maschen (talk) 21:45, 2 December 2012 (UTC)

Can someone versed in Physics review a new article?

New quantum theory is a new article and I believe it is physics related (not too much science background) but it definitely needs attention. Hell In A Bucket (talk) 19:32, 2 December 2012 (UTC)

Paper looks amateurish. It appears to be someone making an article out of their own paper published in a journal of dubious quality. Appears to be pseudosciency and non-notable considering it was only published this month. Not sure if the paper is open access, it's a copyvio if not. IRWolfie- (talk) 19:48, 2 December 2012 (UTC)

That was my main concerns here too but I figured I wasn't qualified to really say one way or another. Hell In A Bucket (talk) 19:50, 2 December 2012 (UTC)

Someone might consider looking at the images as well, such as File:FIGURE_1_PHOTON.png since they are inaccurate and appear to be in the same paper. IRWolfie- (talk) 19:55, 2 December 2012 (UTC)

After the original article is deleted that is. It looks like the article will need to go to AfD. IRWolfie- (talk) 19:59, 2 December 2012 (UTC)

The material is pseudoscience, and should be deleted due to lack of notability if not for another reason. Waleswatcher (talk) 20:45, 2 December 2012 (UTC)

This material is a verbatim copy of the original paper (at any rate the leading paragraphs were - I didn't examine the whole article). It has been flagged for deletion on account of breach of copyright. Martinvl (talk) 21:51, 2 December 2012 (UTC)

I'ts been nominated but I expect it to be declined as it appears they have submitted for permission via email for it's use. Hell In A Bucket (talk) 21:52, 2 December 2012 (UTC)

It has been declined. Maschen (talk) 22:12, 2 December 2012 (UTC)

~~Take it to Afd.~~ Already done. Xxanthippe (talk) 22:45, 2 December 2012 (UTC).

(edit conflict) I declined the copyvio speedy because OTRS permission is claimed, with a ticket number; but I have taken it to AfD as original research, comments welcome at Wikipedia:Articles for deletion/New quantum theory. JohnCD (talk) 22:49, 2 December 2012 (UTC)

template:IsaacNewtonSegments

{{IsaacNewtonSegments}} has been nominated for renaming, see template talk:IsaacNewtonSegments -- 70.24.245.16 (talk) 13:02, 4 December 2012 (UTC)

Combustion models for CFD

Found another one that looks like should get a eye from the Physics community. Hell In A Bucket (talk) 14:10, 4 December 2012 (UTC)

This is just one in a whole series by several authors, all referring to a book by Versteeg & Malalasekera, see [1] and most/all of them problematic. The last day Uncertainty and errors in cfd simulation and Boundary condition implementation in CFD were deleted as copyright violations. -- Crowsnest (talk) 14:22, 4 December 2012 (UTC)

The subject matter looks OK to me - see this paper. The article however leaves a lot to be desired; if it is the start of a new article, I can't really see where the author is going, also nothing is Wikilinked. If the article does not get developed, I think that it is one that can be deleted - it doesn't really tell me anything. If however this article is full of copyright problems (as with others as observed by Crowsnest), it should get the big chop. Martinvl (talk) 14:29, 4 December 2012 (UTC)

Thanks for looking into things, I just know some of the new articles slip through the cracks and they balloon so I bring it to the peeps here. Sorry to bug and happy editing Hell In A Bucket (talk) 14:32, 4 December 2012 (UTC)

Alan Guth's proposal regarding the big bang

Alan Guth proposed that the big bang explosion was caused by the reversal of gravity. When I considered the idea I first thought that he meant that gravity became negative. If so, using the equation A(acceleration) = D(distance) / T(time) squared. If A is negative then, unless D is negative (which seems unlikely) T squared would have to be negative and T would have to equal i. This is hard to understand. After further thought it occurred to me that magnetism can be either positive or negative and perhaps gravity can also be positive or negative. I assume this has long since occurred to others; am I correct? Sui docuit (talk) 16:30, 6 December 2012 (UTC)Sui docuit

You are looking at the wrong equation. You should not be asking about this subject until you have some basic understanding of Newton's law of universal gravitation and Newton's laws of motion. After that you should study special relativity and then general relativity. This should take you at least ten years (probably much more). After that, you may reasonably ask your question at Wikipedia:Reference desk/Science. In other words, you are getting WAY ahead of yourself. JRSpriggs (talk) 05:32, 7 December 2012 (UTC)

Proposal: for User:Damorbel to be community-banned from all articles and talk pages on thermodynamics.

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

This discussion has degenerated into mudslinging and should be continued at WP:AN, if anywhere.

... because enough is enough. (Most recently, recent edits at Talk:Boltzmann constant, eg [2])

No, I know, I shouldn't try to talk him through his misconceptions, and get him to see the points he's been missing. Enough Arbcom decisions have laid down that's not what WP talk pages are to be used for. One ought to just say WP:RS or no discussion. But particularly in Physics, it's so much about understanding how it all fits together, one always feels that with a bit of a discussion, at least we can make sure everyone editing is at least starting from the same square one, understanding each other's perspectives, so that discussion of how to take the article will at least be informed. Even if it's not what talk pages are for, usually that can be concluded in a couple of back and forth responses, and it's worth it because misconceptions can get identified, and editing on the page can move forward with a much better consensus idea of what it's all about.

Except with Damorbel (talk · contribs). It's not just me -- wherever he edits, there end up being walls of text on the talk pages, as people try to explain him basic thermal physics, and he just refuses to get it.

In particular he has an idée fixe that temperature is the average kinetic energy of a molecule -- even if there's just one molecule -- that comes back again and again, and nothing will shift him from it.

So I'm asking the community: is it time to say enough is enough, that some minimum level of competence and cluefulness (or at least ability to learn, or to be a useful Wikipedian) is required, and that regrettably, at least in the area of thermodynamics, Damorbel just appears not to have it? (Either that, or else has been deliberately trolling us for the last three years).

I have never put up a request like this before, and I hope never to have to again, but I simply don't know what else to do. Jheald (talk) 21:29, 8 December 2012 (UTC)

Technicality: This isn't the correct place to propose a community ban. The correct location is the administrators noticeboard. IRWolfie- (talk) 22:02, 8 December 2012 (UTC)

(ec) True. But this is the place where people know about physics, and have the subject-area expertise to discuss whether this should be taken up as a way forward (if necessary, then going on to WP:AN after having sounded out what the people who know about physics here think). Jheald (talk) 22:21, 8 December 2012 (UTC)

Quite true. But it is useful to alert the people here that this is coming on. It sounds as if there may be a case for a ban. Xxanthippe (talk) 22:18, 8 December 2012 (UTC).

I fully agree with JHeald's description of Damorbel's behavior, but I don't want to assign motives. The main problem is the endless chatter that occurs when people (myself included until a few weeks ago) persist in trying to reason with Damorbel on a talk page. Disruptive editing of articles themselves is less of a problem on the pages I have been involved with. PAR (talk) 00:07, 9 December 2012 (UTC)

I agree with JHeald's suggestion. I find Damorbel to have a habit of repeatedly making disruptive edits to articles. Also, Damorbel has great skill at luring others into futile discussion on talk pages. I favour steps to ban Damorbel from thermodynamics and related articles and talk pages.Chjoaygame (talk) 03:30, 9 December 2012 (UTC)

I also am afraid I agree that Damorbel is a gigantic waste of time. He cannot be ignored because he makes changes to articles. He cannot be taught because he has certain ideas that cannot be quashed no matter how many examples he is given. Eventually you realize that you're dealing with a master troll. A stupid person would have given up long ago. A clever person would have learned something. It takes a certain kind of genius to appear forever almost able to grasp a concept that he never will grasp, and will always actually actively refuse to grasp. It takes real talent to do that. It takes a certain Jesuitical or Talmudic insight and bent. Soon you see that the argument game itself, is what appeals. And not (alas) making the thermodynamics articles more transparent for other people. Those of us trying to do that (thankless enough) job, are instead endlessly retarded, embroiled, enmeshed, ensnared, entangled, by Damorbel. We are sunk, slowed, stuck down, mired, bogged, hung up, set back, and trapped by Damorbel. Thixocoagulated forever in viscous dubious decelerating detaining debate. Why? Please god let it end... S B H arris 06:48, 9 December 2012 (UTC)

Such situations are not unprecedented. See the User:Logger9 saga. Xxanthippe (talk) 09:01, 9 December 2012 (UTC).

NOT THANKLESS ... I'm not an editor, I'm an END-USER ... don't you dare think there aren't millions of us out here who don't appreciate and DEEPLY respect the efforts of those who do edit ... (thanx) x 10^23. Watchwolf49z (talk) 13:57, 9 December 2012 (UTC)

I haven't been involved in any of those discussions (thank God), but I notice that Damorbel's edit count is very unusual: 90% of the edits were to talk or user talk pages. Just 7% were to articles - a total of just 92 edits since 2008, 41 of which were reverts! RockMagnetist (talk) 16:44, 9 December 2012 (UTC)

It does seem to me, however, that some of the other contributors to these discussions should recall that one of the good practices for talk pages is "Be concise". RockMagnetist (talk) 16:50, 9 December 2012 (UTC)

After reading Talk:Boltzmann constant, I definitely hope that your proposal to ban Damorbel is successful. He or she is extremely ignorant of rather basic concepts in thermodynamics, yet aggressively self-confident ... the kind of editor who makes our valuable editors want to quit wikipedia and find a new hobby. --Steve (talk) 14:52, 10 December 2012 (UTC)

I looked at his User page. It is a sandbox with a few thermodynamic equations that have not changed for over three years. I expect a person to tell us a bit about themselves on their talk pages - they don't have to reveal too many personal details - examples being User:TimothyRias and User:Jc3s5h, both of whom have revealed a lot about themselves without revealing the real life identity. This makes discussions with them a lot easier. Damorbel however has chosen to reveal absolutely nothing about himself (or herself). Martinvl (talk) 15:25, 10 December 2012 (UTC)

Damorbel should be banned after looking at his/her talk page, article talk pages, editing history/count etc... Not involved (much); I recently posted a reply to one of Damorbel's comments on talk:Boltzmann constant which will probably not help anything, so given such ignorance ~~I'll just stay out of it~~... Maschen (talk) 15:27, 10 December 2012 (UTC)

Jheald so you wish to get me banned!! You write:

... I know, I shouldn't try to talk him through his misconceptions..

Then why do you do it?

What you are doing here is trying to convert a discussion on the Boltzmann constant article to a personal attack on another contributor. For example, not content with failing to respond to my contribution (above link) you go further when you write in opening this section:-

In particular he has an idée fixe that temperature is the average kinetic energy of a molecule -- even if there's just one molecule -- that comes back again and again, and nothing will shift him from it.

Jheald, if you thought for moment you would realise that my argument is correct. The temperature of a particle is related to its energy by the Boltzmann constant, ja oder nein? Because, above a certain density, particles in gas liquid or solid state exchange energy by collision (gas) vibration (solid) and both collision and vibration (liquid); the result is that, when the energy exchange is truly random, as in the conditions for the Maxwell Boltzmann distribution, all the particles have the same average energy over time thus the same temperature. Of course the particles do not have the same energy at the same time, only a true innocent would think that.

You have chosen a strange place to discuss this and I wouldn't recomend it to anybody, but then you raised the matter and I am fully confident in my response.

PS It is only the particle energy that defines its temperature; this was noticed by Einstein when commenting on the motion of pollen particles in his 1905 paper on Brownian motion. --Damorbel (talk) 09:09, 12 December 2012 (UTC)

Einstein's paper (1905) predated the publication of the concept of quantum mechanics (Schroedinger, Dirac etc in the 1920s). Martinvl (talk) 09:26, 12 December 2012 (UTC)

The fact of this matter is that Jheald was unable to make a constructive response to discussion on the Boltzmann constant article and is trying to (Shock! - Horror!) kick the table over. --Damorbel (talk) 10:56, 12 December 2012 (UTC)

Correct: he didn't make one constructive response - he made lots of very clear constructive responses very patiently in excruciating detail, as did several other editors. Thanks for proving the points made by others above in your last two posts.

It's a real shame you can't think outside the box; that you may be the one who is wrong and not the rest of the world. Even at high school/A-level (at least in my experience) when kinetic theory is introduced you are told that the temperature of one molecule is meaningless, and that the average kinetic energy (of many particles) corresponds to kT/2 for each degree of freedom. Maschen (talk) 11:05, 12 December 2012 (UTC)

Maschen, you write:-

the average kinetic energy corresponds to kT/2 for each degree of freedom.

And what then is the average kinetic energy of a particle if it isn't its temperature? You make no comment on the fact that the energy of a particle in the "free (kinetic) energy exchange" or "equilibrium conditions" of the current discusssion is independent of the particle size, that was the main point in Einstein's paper, whether the particle was a molecule of water or a pollen grain billions of times more massive than a water molecule, the two would still have the same (time averaged) kinetic energy and thus the same temperature. --Damorbel (talk) 11:22, 12 December 2012 (UTC)

Clearly there is no point explaining it to you. Bye. Maschen (talk) 11:32, 12 December 2012 (UTC)

Sorry, I don't understand your difficulty. Are you saying that the average kinetic energy of a pollen grain is not connected to its temperature? O r perhaps the kinetic energy of a particle is a function of its size?

To me this doesn't seem very complicated and I would like to discover why you are having difficulty grasping what I am arguing. Please don't " Bye ", we both lose that way. --Damorbel (talk) 11:46, 12 December 2012 (UTC)

I'm conflicted on this. On the one hand, most of Damorbel's edits are to talk pages, which is really pretty harmless. You quickly learn it's a waste of time to engage with him - he has some fundamental misunderstandings of thermal physics, and doesn't seem capable of learning. His edits to the articles themselves are often reverts (that have sometimes been justified), or well-meaning but inept and failed attempts to improve the articles. I'd say his contributions are clearly net negative. But is that really sufficient justification for a ban? I'm not sure. Waleswatcher (talk) 13:20, 12 December 2012 (UTC)

Indeed you have a conflict here. On the one hand you think you are different from Damorbel because you think you are smarter than the average bear while he is not. On the other hand you recognize in Damorbel a spirit kindred to your own, in how you post in the Wikipedia.Chjoaygame (talk) 05:31, 13 December 2012 (UTC)

You've just weakened your own case - you want to ban Damorbel for being disruptive/not constructive/uncivil, and then you behave that way yourself. I post "in the Wikipedia" almost exclusively on topics on which I am an expert. Damorbel's real problem - and yours as well - is a combination of lack of understanding of the material and misplaced confidence.

As I said, I think Damorbel's contribution to wikipedia (at least the part I'm familiar with) is net negative. As such, there is some benefit to banning him. It's just that I'm not sure that's sufficient justification for such a ban. And indeed, all of that goes almost equally for you as well. Waleswatcher (talk) 07:03, 13 December 2012 (UTC)

Is this Wiki policy?

Jheald writes (this section, opening statement.)

So I'm asking the community: is it time to say enough is enough, that some minimum level of competence and cluefulness (or at least ability to learn, or to be a useful Wikipedian) is required, and that regrettably, at least in the area of thermodynamics, Damorbel just appears not to have it? (Either that, or else has been deliberately trolling us for the last three years).

I read this as an attempt to take ownership of a Wiki article by restricting who may contribute. Almost all my contibutions are accompanied by Talk Page sections, the vast majority are Talk Page sections; the idea being to sort out technicalities before changing the article. What I am getting from Jheald and others is this kind of sterile argument:-

wherever he edits, there end up being walls of text on the talk pages, as people try to explain him basic thermal physics, and he just refuses to get it.

No logic, no science, just playground banter.

Come on Jheald, I am expecting better "stuff" from you!--Damorbel (talk) 12:07, 12 December 2012 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

The Simulation hypothesis article may benefit from this link.

I think that this article may benefit from this link. However, since I am not a science expert I don't understand it very well. I'm not sure if it's proving or disproving the simulation hypothesis. Someone else may be able to make sense of it. Thanks. (This same comment is posted on the talk page of that article.) Lighthead ^þ 23:15, 10 December 2012 (UTC)

A snap judgement. It's drivel. Xxanthippe (talk) 23:19, 10 December 2012 (UTC).

I agree that it's drivel. The sort of drivel that justifies the abolition of philosophy departments of universities. Because it's very poor philosophy, perhaps better called pseudo-philosophy.Chjoaygame (talk) 23:47, 10 December 2012 (UTC)

But then philosophy is completely useless as Sidney Coleman pointed out: "A thousand philosophers working for a thousand years could not come up with anything as strange as quantum theory". Count Iblis (talk) 00:44, 11 December 2012 (UTC)

Newton thought he was a philosopher. Yes, a natural philosopher, but still a philosopher. His philosophy, relying on Aristotle, taught him that his law of gravity couldn't be right. He knew that it lacked the continuity property, nowadays supplied by field theory, but he didn't know then how to formulate that. Of course today we are all much cleverer than useless old Newton. As for quantum theory being "strange"? Strange to whom?Chjoaygame (talk) 04:38, 11 December 2012 (UTC)

I don't see how this can be dismissed so easily. It may be more philosophy than physics, but it doesn't look like drivel to me and its authors seem to be respected physicists (Martin Savage has several publications with more than a hundred citations). Instead of judging it ourselves, we should ask the usual questions about the existence of independent sources. There already is one - the Science Daily article. RockMagnetist (talk) 02:49, 11 December 2012 (UTC)

The Wikipedia policy requires reliable sources; it is reliability for the particular purpose, not independence, that is required. The Science Daily article, I would say, is a perfect example of a source that is not a reliable source for the particular purpose.Chjoaygame (talk) 04:38, 11 December 2012 (UTC)

I don't know how reliable Science Daily is. The requirements for sources depend on whether you're trying to say the theory is true or just say that it has been proposed. The paper has attracted a lot of attention on the web, but it was only published last month, so it's a bit early for the academic responses. Probably the best approach is to wait a while. RockMagnetist (talk) 05:44, 11 December 2012 (UTC)

Whatever; it makes sense to wait. As to the rejection of material from Science Daily, Science Daily is just a middleman news provider. Their news is always backed up by a primary source. Lighthead ^þ 06:21, 11 December 2012 (UTC)

My interpretation is that a reliable source is one that you know is reliable. If you don't know if a source is reliable, then I would say that you have to allow the possibility that it is unreliable. That makes it not reliable. How do you know if a source is reliable? You have to check it against all the rest of what you know, and against other relevant sources, especially ones that you know are reliable. Of course that puts weight on what you know; in the end, the Wikipedia must depend to an extent on the editors' actually knowing something about what they are editing. An ignorant editor cannot be a reliable one. All knowledge is of only a degree of reliability; one can't get past that; the Wikpedia cannot be perfect. In general, one can't trust academic responses to be reliable. The present case is an example. If Science Daily's news is backed up by a primary source, the reliability of the primary source needs checking. In general primary sources are not automatically assumed to be reliable; the Wikipedia policy warns against editors' assuming they are so. I don't think the Wikipedia should be a sort of websearcher; people who want a websearch should try Google or somesuch.

I think both of you finally conclude that it makes sense to wait. I think, if I read that aright, then I agree that it makes sense to wait.Chjoaygame (talk) 07:33, 11 December 2012 (UTC)

Heim theory

This article is obvious fringe science and should be deleted for lack of notability. If others agree, perhaps we can start the AfD process. Waleswatcher (talk) 07:09, 13 December 2012 (UTC)

I have been saying that for years, but the article has strong defenders. Xxanthippe (talk) 07:12, 13 December 2012 (UTC).

Has it been proposed for deletion before, and there was no consensus? Wiki has pretty clear policies on this. There are literally hundreds of such crackpot theories out there, and none should have wiki pages (or at the very least it should be made crystal clear in the article that this is crackpot stuff). Waleswatcher (talk) 07:16, 13 December 2012 (UTC)

AFD

Nominated for a 2nd time - input welcome. Maschen (talk) 08:36, 13 December 2012 (UTC)

It's the third time, actually. And I'm not sure I managed to all your AfD formatting errors. If you're going to nominate an article for deletion, use the templates provided. — Arthur Rubin (talk) 11:18, 13 December 2012 (UTC)

Well I apologize for completely missing out the 2nd discussion and "all" the errors, I couldn't find any other template at the time better than the one I did post in the article. Nevertheless thanks for fixing my mess... I haven’t nominated anything for deletion before which already had be pre-nominated (this is the 2nd time I've ever nominated for deletion actually). Maschen (talk) 16:57, 13 December 2012 (UTC)

Fractional quantum mechanics + Fractional Schrödinger equation are unbalanced

This article is written (almost) entirely from Nick Laskin's (user:Nlaskin) point of veiw - so I added the {{unbalanced}} tag. WP:VANITY is clearly evident. I'll look for additional sources in time (can't right now), but if anyone else has some refs please add... Maschen (talk) 08:59, 13 December 2012 (UTC)

Newbie Questions

How can I find out who the "professional" overseer is for the article Coriolis effect? There seems to be substantial and pervasive errors throughout the article, and rather large group of editors hellbent on not letting these be corrected. If one ignores gravity, then one cannot observe any it's effects, including the Coriolis effect. Watchwolf49z (talk) 14:52, 1 December 2012 (UTC)

There is no "professional overseer". I'm afraid the "rather large group of editors" is all that there is. You can learn more at Wikipedia:Consensus...

The Coriolis effect is not a consequence of gravity. (People who say "The Coriolis effect causes northern-hemisphere hurricanes to spin counterclockwise" are not speaking 100% precisely; they should say "The Coriolis effect interacting with gravity, sunlight, etc. causes northern-hemisphere hurricanes to spin counterclockwise.")

Your comments on the talk page do point towards legitimate problems with the article, in my opinion. For example, should the phrase "Coriolis force" be changed to "Coriolis (pseudo)force" everywhere in the article? Maybe ... it would avoid some misunderstandings, but on the other hand it could get annoying. I'm not sure what's best. And yes, some descriptions are rather dense and could be clarified. There are various possible preconceptions and misunderstandings that the article does not do a good job of setting right.

Yet, the "rather large group of editors" are by and large extremely knowledgeable and working in good faith to have an article that is both clear and accurate ... you should not view them as enemies but collaborators :-) --Steve (talk) 15:48, 1 December 2012 (UTC)

Watchwolf49z, I've posted some comments there. I don't agree with your assessment. I am a professional physicist and a specialist in gravity, if that helps. Waleswatcher (talk) 17:29, 1 December 2012 (UTC)

I see I've come to the right place, all good advice. I'm glad my sense of impending doom was not ill-founded. Watchwolf49z (talk) 20:16, 1 December 2012 (UTC)

- - - 2-shay! Let's hear it 4 doom. God I'm glad I'm not alone.Magneticlifeform (talk) 23:40, 14 December 2012 (UTC)

Let us resolve it here and now

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

This isn't the place to resolve understanding...

Some contributors claim that I am so ignorant that my contributions are so disruptive and that I should be banned from editing.

So let us resolve the matter.

Basing the resolution on the complaint made above by Jheald and endosed by PAR; S B H arris; Martinvl; Steve; Maschen and Chjoaygame that :-

[Damorbel]...has an idée fixe that temperature is the average kinetic energy of a molecule -- even if there's just one molecule -- that comes back again and again, and nothing will shift him from it.

So I summarise my argument:-

"In a system of particles in thermal equilibrium, with an energy content giving rise to a temperature T the temperature is independent of the number of particles N and extends through the equipartition of energy, to any subset n of N that is excited at that temperature."

The difficulty, as far as I can see, that user Jheald et al have is not when n is large (>10¹⁰) but as n -> 1. The relation between the energy of a particle and its temperature is the Boltzmann constant, this relationship can be extended to complex molecules with more than the three degrees of freedom, because the equipartition of energy extends to all degrees of freedom that are excited at the relevant temperature.

The matter will be resolved if anybody, let alone Jheald et al, can show that the equipartition of energy does not apply in the given equilibrium conditions or that the science behind the Boltzmann constant does not apply to particles in general (including pollen grains!).

I suggest Jheald et al assist in resolving this matter here and now. If it isn't resolved here I shall be more than happy to resolve it at Wikipedia:AN. --Damorbel (talk) 09:58, 13 December 2012 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

These responses to thermodynamics are leading nowhere...

response 1

I'm just a newbee here, but aren't we required to fully reference all our statements, even on talk pages? I'm kinda of in the same position as you right now, and my "opposition" is perfectly correct making me dig up peer review scientific literature to back my position. My claim is extrordinary, it absolutely requires extrordinary references. I'd love to debate these people on the matter, but Wikipedia is the wrong place for that. Watchwolf49z (talk) 14:29, 13 December 2012 (UTC)

If you need an explanation, just ask. Providing a complete introduction with every contribution without a point of departure is not really feasible. --Damorbel (talk) 15:56, 13 December 2012 (UTC)

response 2

Damorbel, your summary appears to be correct. I quote from Kittel:

Temperature is precisely defined only for a system in thermal equilibrium with a heat bath: The temperature of a system A, however small, is defined as equal to the temperature of a very large heat reservoir B with which the system is in equilibrium and in thermal contact. Thermal contact means that A and B can exchange energy, although insulated from the outer world.

The system A may even be a single atom of a gas. Then the reservoir B is composed of all the other atoms of the gas, along with perhaps the walls of the common container. We do not speak of the single atom as having a fluctuating temperature that tracks its fluctuating kinetic energy.
— Kittel, Charles (1988). "Temperature Fluctuation: An Oxymoron". Physics Today. 41 (3): 93. doi:10.1063/1.2811420.

RockMagnetist (talk) 16:46, 13 December 2012 (UTC)

The above statement is true for the standard thermodynamic definition of temperature. However, this definition has been criticized because it does not allow for the intuitive notion of thermal fluctuations. See Mandelbrot, Benoit B. (1989). "Temperature Fluctuation: A Well-Defined and Unavoidable Notion". Physics Today. 42 (1): 71. doi:10.1063/1.2810881. The issue has been much debated since then, and there have been attempts to define temperature to allow for fluctuations. RockMagnetist (talk) 16:50, 13 December 2012 (UTC)

We do not speak of the single atom as having a fluctuating temperature that tracks its fluctuating kinetic energy. Indeed. But Damorbel does, because to Damorbel, temperature IS kinetic energy even for single atoms. Thus, to Damorbel, as this single atom changed kinetic energy over time in a random fashion, it would also change its temperature, which would be a single function of time T(t). But of course, this is wrong. The temperature of the single atom (defined as its equilibrium contact portion of the reservoir's energy) is the time-average of its kinetic energy <E>. One atom can have a temperature if it has a kinetic energy that changes over time as a result of contact with other atoms in a thermal collection (indeed, we can follow around an individual atom in any sample of gas and look at that number). But an atom with no interactions and one unchanging kinetic energy, cannot have a defined temperature, as it has no entropy. Temperature is a statistical thing. You have to average over more than one state. That can be one state in time, or it can be more than one state in energy. But it must exceed one state and be at least two states. Damorbel actually seems to understand this point for entropy, but 1/temperature is merely a measure of how much entropy changes in a system per unit of increased energy. If the system has energy but NO entropy (the case with one atom moving along, at one unchanging velocity, forever), it has no defined temperature. 1/T = dS/dE = 0 because dS = 0. Thus 1/T = 0 and T is infinite. So the notion of T makes no sense in that case. Which is why we can use single atoms flying along at single velocities to heat any object to any temperature we like. In a sense, they have an infinite temperature since there is no entropy to worry about when we extract their kinetic energy to do work. They also have no "thermal energy content." Their motion transmits energy, but the energy is not "heat" (heat energy has a residuum energy that cannot be used to do work, without paying the entropy cost in some other way). The kinetic energy of single atoms moving at a single velocity is not degraded energy. And, in fact, such energy can be made to go away entirely by simply chaning reference frames, so it is clear that the universe doesn't care about some entropy disappearing. However, a collection of atoms at different velocities has no reference frame where all atoms are moving at zero velocity. In some frame they are all going in different directions, and that's the one where you see their entropy, which represents kinetic energy that has limitations as to how much work you can get from it.

By contrast, the kinetic energy of a single atom moving at a single velocity forever, can be turned into work at 100% efficiency. And so on and so on. If you give such an atom with unchanging energy a finite temperature (either at any instant in time, or as considering an atom what keeps the same energy over time), none of those things are true. S B H arris 23:08, 13 December 2012 (UTC)

Maybe that is an accurate summary of Damorbel's views, but I don't see what can be gained by discussing them here. I have looked at the discussions in some of those articles, and found a lot of editors making long-winded statements and attacking each other as well as Damorbel. It just doesn't seem worth my time to sort out the arguments. I suggest focussing on references. In the Boltzmann constant article, a single citation was worth a page of argument. RockMagnetist (talk) 23:35, 13 December 2012 (UTC)

So you say now. But wait until Damorbel simply ignores that citation. It contradicts him, therefore he will not accept it. S B H arris 00:03, 14 December 2012 (UTC)

Well, I have often found that a few good citations can break an impasse. RockMagnetist (talk) 02:37, 14 December 2012 (UTC)

There is a diversity of viewpoints here, some more or less relevant to different articles. There are already many good citations in the relevant articles. Citations alone will not be enough. Understanding matters too.Chjoaygame (talk) 03:23, 14 December 2012 (UTC)

response 3

The lead of this section by Damorbel adverts to the proposal to ban Damorbel and seems to imply that allegation of ignorance is the only ground for it. There are other grounds for the proposal to ban Damorbel besides that he is alleged to be ignorant. The other grounds lie in his manner of editing. This point needs to be made here because Darmorbel's lead to this section adverts to the proposal.

But I will not here address the proposal or its grounds. Damorbel's lead here intends to focus on his views on temperature as a question of physics, and that is what I am addressing here. I do not know whether it will be considered useful to work on this question here, but I fear that silence might be construed as consent. I will not try to put all the picture here and now, but will wait to see if other editors are interested in this section.

Damorbel summarizes his argument in the lead to this section above, starting with the phrase "In a system of particles in thermal equilibrium, ..." In starting so, Damorbel is proposing a particular point of view, that of the kinetic theory of gases and perhaps more or less of statistical mechanics, which is focused on systems of particles, as indicated by his starting phrase just quoted. I will argue here that there are other points of view, and I will give some hint that they are more basic to the present Wikipedia articles than the point of view here advocated by Darmorbel. The main other point of view is that of plain thermodynamics, which avoids mention of particles.

That viewpoint, advocated here by Damorbel, is perhaps partly or wholly accepted by some authorities who like to teach their students in a particular way, which may be called the way of thermal physics. Kittel & Kroemer (1969/1980) and Reif (1965) are examples. It so happens that these two texts have been cited for the definition of heat in the current version of the article on heat. This is an accident of Wikipedia editing history, that the definition was taken from those authors, because they were favoured by editors with clout at the time of creation of the current version. Other definitions have been favoured and cited by other editors previously. It cannot be taken as settled that the way of thermal physics is the one right point of view.

The way of thermal physics takes a pedagogical viewpoint, that thermodynamics and statistical mechanics should be taught together, so that the student will have a strong feel for their common elements. It is different from the main alternative viewpoint, that thermodynamics should be taught before statistical mechanics, as a separate subject, for reasons which I will not right here state, but will state later.

The distinction between thermodynamics and statistical mechanics is recognized by many authorities on thermodynamics. For example Fowler and Guggenheim (Fowler, R., Guggenheim, E.A. (1939). Statistical Thermodynamics, Cambridge University Press, Canbridge UK.) on page 3 write about the fundamental assumption of statistical mechanics:

'Assumption 1. The atomic constitution of matter.

To-day, this hardly ranks as an assumption, but it is relevant to start by recalling that it is made, since any reference to atomic constitution is foreign to classical thermodynamics.

Fowler and Guggenheim are here distinguishing two viewpoints, that of statistical mechanics and that of classical thermodynamics.

Reif (1965) is a member of the thermal physics school of pedagogy, but he nevertheless recognizes that thermodynamics may be considered as a subject separate from statistical mechanics. This recognition is stated in the opening of the preface of his textbook, on page vii. I will not copy this material here, because it is too copious, but I will mention that Reif says that he thinks his pedagogical approach is clearer and more illuminating than the other pedagogical approach.

Kittel & Kroemer (1969/1980) are also members of the thermal physics school of pedagogy. They start with a definition of entropy as measuring the number of quantum states accessible to a system. They do not spend words making the distinction between thermodynamics and statistical mechanics. They simply announce on page 1 that their "approach to thermal physics differs from the tradition followed in beginning physics courses."

Some respected texts make it clear that they favour teaching thermodynamics as a distinct subject without essential reference to statistical mechanics. Examples include Adkins (1968/1983), Buchdahl (1966), and Pippard (1957). I will here quote only Adkins (1968/1983) on page xi: "many books and courses on thermal physics attempt to develop classical thermodynamics and statistical mechanics side by side. ... ... it is best to teach classical thermodynamics first and separately, for the ability to use it well depends largely on knowing what it can achieve without appealing to the microscopic nature of things."

In my judgement, Damorbel is here advocating putting the kinetic theory of gases and to some extent statistical mechanics as primary, with little or no recognition of the purely thermodynamic point of view. As I read Darmorbel, he intends to deny that there is a weighty distinction between the thermodynamic viewpoint and that which he advocates which can be labelled that of the kinetic theory of gases and perhaps that of statistical mechanics.

Some editors here think that the thermodynamic point of view has some merit, and propose to define temperature by considering a thermodynamic system defined simply by macroscopic thermodynamic quantities, especially internal energy and entropy. This approach was proposed by Gibbs. It defines temperature in terms of the functions of state of the system so defined, without reference to its microscopic constitution.

In my judgement, this thermodynamic point of view has been considered by the majority consensus of editors here as the primary one for the definition of temperature. In my judgment, Damorbel's lead to this present section is seeking to overthrow this consensus and to replace it with a definition of temperature based in the kinetic theory of gases and in statistical mechanics.

There are textbooks that explicitly admit two distinct definitions of temperature, one based in thermodynamics, the other based in the kinetic theory of gases. An example is Chapman, S., Cowling, T.G. (1939/1970), The Mathematical Theory of Non-uniform Gases. An Account of the Kinetic Theory of Viscosity, Thermal Conduction and Diffusion in Gases, Cambridge University Press, Cambridge UK, p. 37. They regard it as a duty to show that the two definitions are properly compatible.Chjoaygame (talk) 04:25, 14 December 2012 (UTC)

There is no doubt that thermodynamics makes sense independently of statistical mechanics. But that doesn't mean that the wiki article on such fundamental and basic concepts as heat (for example) should not describe it using stat mech. On the contrary - stat mech is more modern, more fundamental, and more exact than thermodynamics. As far as we know, it is the correct way of viewing the world, while thermodynamics is merely an approximate description.

"In my judgement, this thermodynamic point of view has been considered by the majority consensus of editors here as the primary one for the definition of temperature." That is certainly not the case in the past year or so of edits to those articles, quite the contrary. Before that, I can't comment. As for Damorbel, the problem is not that he insists on stat mech at the expense of thermo, it's a lack of understanding. Waleswatcher (talk) 07:14, 14 December 2012 (UTC)

Damorbel's most focal idea, I think, is that temperature should be defined on the basis of the kinetic theory of gases or perhaps of statistical mechanics: that temperature should be primarily defined by the average kinetic energy of particles. Judging from this comment, Waleswatcher seems to think that temperature should be defined through thermodynamic quantities: "The true definition of temperature is T=dE/dS. But since both E and S (contrary to PAR) are defined by averages and/or expectation values, T is an average quantity too." One might read this comment by Waleswatcher as taking E and S as statistical mechanical quantities, or even perhaps as quantities of the kinetic theory of gases. But either way, it seems to be contrary to Damorbel's view that temperature is primarily defined in terms of the mean kinetic energy of particles. It is the latter which is the focus of the present section.Chjoaygame (talk) 09:05, 14 December 2012 (UTC)

Waleswatcher's comment just above seems to me to recognize a distinction between thermodynamics and statistical mechanics or the kinetic theory of gases. I think that it may be seen by reading Damorbel's comments, that less focal, though still important in Damorbel's viewpoint, is that it does not recognize such a distinction.Chjoaygame (talk) 09:45, 14 December 2012 (UTC)

There are some interesting issues here, but how is this discussion going to lead to improvements in Wikipedia articles? RockMagnetist (talk) 16:18, 14 December 2012 (UTC)

Exactly. The endless chatter from particular thermodynamics talk pages has simply been moved to this page. What we need is a small group of responsible editors who have a high understanding of thermodynamics and, most importantly, have a knowledge of their own limitations and are willing to compromise with each other, and who are dedicated to improving the articles, rather than edit warring and investing their egos and playing endless games of gotcha on the article talk pages. This small group of editors could repair the articles, and with a small investment of time, keep it that way until the trolls and their fish get tired of the game. Until this happens, the articles are at their mercy. I will try my best to be one of those editors, but I am not going to waste my time beating my head against a brick wall, spitting out troll-hook after troll-hook. PAR (talk) 18:05, 14 December 2012 (UTC)

I closed the previous argument, but I don't want to become the gatekeeper for this page. Anyone else care to do the honors? RockMagnetist (talk) 18:51, 14 December 2012 (UTC)

Yes. M∧Ŝc²ħε И_τlk 18:57, 14 December 2012 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Relevance of Physics articles

I have been very disappointed with the "encyclopaedic" articles on modern and quantum physics. None of those I have viewed meet the standards of an encyclopaedic article per se. An encyclopaedic entry should be elucidatory. Instead, experts offer the circular and internally self-justifying references and arbitrary ellipses of a technical jargon, routinely failing to link these up to their semantic origins.

Writers in this field should undertand that their ellipses and abbreviations are useful only as reminders and exam crammers for the initiated. They are not "encyclopaedic". Technical language is an abbreviated language, and abbreviations, including the semiotic indices of mathematics (formulae, etc), are arbitrarily constructed and necessarily void of meaning.

Writers here must present their texts to the rigorous judgement of common understanding. This means unravelling technical abbreviation or jargon in order to display its meaning or semantic origins. This is a difficult task to accomplish but is a necessary one if writers here wish to meet the standards required for an accomplished encyclopaedic article. (JIJnes (talk) 19:07, 15 December 2012 (UTC))

If you actually want something to be done about it, you should include links to specific articles to be improved. Zueignung (talk) 19:35, 15 December 2012 (UTC)

The same obvious and tired comments "too technical/too much jargon/I know it's a difficult subject but make it understandable for laymen, not just for experts" etc etc always come up on (almost) every physics/maths talk page. Everyone knows these comments, it's far easier said than done, and the best editors (no - I'm not one of them, but Zueignung is) are steadily making such articles more transparent (while the rest of us at least try to...). M∧Ŝc²ħε И_τlk 22:45, 15 December 2012 (UTC)

There is much truth in what JIJns says. One only has to compare the writing in respected physics texts to that in many Wikipedia articles to see the contrast. It heightens one's respect for the authors of those texts. However, Wikipedia can be improved and many fine editors are doing this. Xxanthippe (talk) 22:58, 15 December 2012 (UTC).

Technical language is an abbreviated language, and abbreviations, including the semiotic indices of mathematics (formulae, etc), are arbitrarily constructed and necessarily void of meaning. Nonsense. All language is technical and all language is abbreviation. Semiotic indicies you say? LOL. glad you avoided those. But you forgot you weren't writing for a politically correct academic education journal, which of course is full of its own specific jargon.

All good writing must have an intended audience in mind, complete with supposed level of assumed prior knowledge. Where does it say, please, that this should be uniform across WP in general, and math and sci articles in particular? And what do we suppose our lowest common denominator should be? Reader's Digest was written at 6th grade level. It's rather a long way from there to Lie algebra, mesons or metabolic acidosis. S B H arris 23:37, 15 December 2012 (UTC)

Personally, I don't think the level should be uniform. I think articles on more specialized subjects should use more specialized language and assume more background, because such articles are more used by and useful to experts. The same goes within an article. However, JIJnes is absolutely right that many wiiki articles are written using too much jargon. Much of my recent editing has been to thermal physics articles (like heat, Planck's law, etc.), parts of which (in some cases even the lead and introductory sections) had become nearly incomprehensible even to experts. My main goal has been to make them more comprehensible to non-experts. Waleswatcher (talk) 23:52, 15 December 2012 (UTC)

It's hard. So hard that some college intro physics texts have wrong or bad definitions for things like weight, in an attempt to be transparent. And I don't know how many times I've read in sloppy texts that mass can be converted to energy (after which we presume mass ceases to exist...) It took a long time to fix that on WP.

Anyway we must keep in mind that the audience for many articles is very broad, and second that this is a hypertext medium, not a newspaper, and we need to use the virtues of linking on this very problem. Still, the technicality of subject should control the rapidity of descent into tech language, but not usually affect the tech level we start at in the lede. See the TALK page for heavy water and the compromise we made there. S B H arris 01:18, 16 December 2012 (UTC)

Request for comment: Planck's Law

More help needed on the Planck's law article - The disputes are endless, but I would like to request comment on one specific point, outlined in the Talk:Planck's law#Presence of mass section. Thanks for any help. PAR (talk) 03:32, 18 December 2012 (UTC)

Maybe take a break for a few months on the subject, work on something everyone agrees with. The UBV photometric system stub could be expanded and it seems you folks are the best people for the job. Watchwolf49z (talk) 13:53, 18 December 2012 (UTC)

Stephen Hawking bday

Stephen Hawking has been proposed for the mainpage TFA, but I and others have raised concerns about its preparedness. Is anyone from WP:Physics willing to have a look at Talk:Stephen Hawking and pitch in a hand at adding content as needed? Thanks in advance, SandyGeorgia (Talk) 22:47, 19 December 2012 (UTC)

CPT symmetry

Hi!

I found the article on the CPT theorem needing some serious beefing up. Then, also, it appears (in the article) as if CPT invariance (and Lorentz invariance) is seriously questioned these days. The references include http://arxiv.org/pdf/0801.0287v5.pdf, which seems legitimate enough (tough reading), and also this: http://www.physics.indiana.edu/~kostelec/faq.html. It is by the same author. I don't doubt that the author is serious, but, ..., is this mainstream?

To me, it would seem as "No Lorentz Invariance in Physics" would be much much bigger news than any Higgs boson whatsoever. YohanN7 (talk) 16:44, 20 December 2012 (UTC)

I haven't yet looked at this in detail, but these are my first impressions:

The arXiv paper you mention is a preprint of a paper published in Reviews of Modern Physics, which is a highly reputable journal intended mainly to summarize well-established areas of research in physics. I think it would be surprising if there were any non-mainstream claims made in this paper.
The bit about C violation in the neutrino sector is (I assume) meant to be a comment about Lorentz-violating neutrino oscillations, but as written it's rather cryptic. Neutrino physics is not an area that I'm particularly familiar with, so I can't say whether this comment belongs in the article or not.

So there's nothing in the CPT article that immediately sets off my BS detector, but I agree that as written the article is hard to make sense of. Zueignung (talk) 18:39, 20 December 2012 (UTC)

Yes, the paper, and the author of it seem very solid. I should have formulated what I wrote above differently. But still, experimental results indicating violation of special relativity should have been heard of loudly. I am not questioning the paper, but I am questioning what seems to be the Wikipedia's article's conclusion, namely that CPT likely does not hold. It says, under the heading of CPT Violation, that "Several experimental searches[which?] of such violations have been performed during the last few years and recently there has been some strong evidence for a violation of charge symmetry in that antineutrinos seem to have a different mass from neutrinos.".

At least it should be pointed out that C violation isn't the same as CPT violation. It seems clear that CPT violation implies violation of Lorentz invariance. It is not clear that C violation implies violation of Lorentz invariance. But, then again, different masses for particles and antiparticles seem to break special relativity. I am, b t w (as you will have figured out), not a physicist, just an interested layman. YohanN7 (talk) 19:48, 20 December 2012 (UTC)

There is zero evidence for CPT violation, and if the article suggests otherwise it needs to be re-written. CPT is a consequence of some of the most basic principles of physics, so a violation of it would be big news indeed. Waleswatcher (talk) 20:14, 20 December 2012 (UTC)

I removed the bit about neutrinos since (1) it was evidently causing confusion, and (2) neutrinos are just one of many ways to test for Lorentz violation. Editors are welcome to expand the paragraph into a more balanced summary of tests of Lorentz violation. Zueignung (talk) 21:12, 20 December 2012 (UTC)

Possible hoax about physicist

I'd like to get a few eyes on Alexander Ivanovich Popov. It's up for proposed deletion as a possible hoax. I'm not qualified to evaluate whether the claimed physics accomplishments of this person are plausible. Please have a look and leave feedback at Talk:Alexander Ivanovich Popov. Dcoetzee 23:39, 23 December 2012 (UTC)

Discussion at Wikipedia talk:Manual of Style/Dates and numbers#Expressing uncertainty

You are invited to join the discussion at Wikipedia talk:Manual of Style/Dates and numbers#Expressing uncertainty. — A. di M. 10:54, 24 December 2012 (UTC)

Gallery in the Kármán vortex street article

There is currently an ongoing discussion on whether there should or should not be a gallery in the Kármán vortex street article. The discussion is located at Talk:Kármán vortex street#Gallery. As this article is within this WikiProject, I thought I would put this here to get some more discussion as I am so far the only person to have weighed in (and it seemed a little too minor to take to RfC quite yet). Inks.LWC (talk) 22:54, 24 December 2012 (UTC)